This directory contains the data files for the typical meteorological year (TMY) data sets derived from the 1961-1990 and 1991-2005 National Solar Radiation Data Base (NSRDB) archives. Because they are based on more recent and accurate data, these new TMY3 data sets are recommended for use in place of earlier TMY2 data. The TMY3 data set contains data for 1020 locations, compared with 239 for the TMY2 data set.

The TMY3s are data sets of hourly values of solar radiation and meteorological elements for a 1-year period. Their intended use is for computer simulations of solar energy conversion systems and building systems to facilitate performance comparisons of different system types, configurations, and locations in the United States and its territories. Because they represent typical rather than extreme conditions, they are not suited for designing systems to meet the worst-case conditions occurring at a location.

TMY, TMY2 and TMY3 data sets cannot be used interchangeably because of differences in time (solar versus local), formats, elements, and units. Unless they are revised, computer programs designed for TMY and TMY2 data will not work with TMY3 data. NREL provides a conversion program to reformat TMY3 data to TMY2 data (see the Software section below.)

The TMY3 data sets and manual were produced by NREL's Electric Systems Center under the Solar Resource Characterization Project, which is funded and monitored by the U.S. Department of Energy's Energy Efficiency and Renewable Energy Office.

20-AUG-2008 NOTICE

All illuminance and luminance values for all TMY3 stations from January 2 to 31 should be multiplied by 100 to obtain the correct units of Lux and Candela per square meter. NREL will be posting a corrected data set in the near future.

The Data

• Individual Station Files
  • In alphabetical order by state and city.
  
  
  • In numerical order by USAFN number.



• All Stations in a Single Compressed File:
  • tmy3.tar.gz - 228.7 MB

    NOTE: In some browsers, file may download as tmy3.tar.tar. Rename file to tmy3.tar.gz before decompressing.
    Decompress using Filzip, WinZip, or similar program in Windows; Stuffit Expander on Macintosh; and the command "gunzip" on Unix systems.

• TMY3_StationsMeta.csv
  • TMY3_StationsMetaMeta.doc
• Errata

Documentation

• TMY3 User's Manual (PDF)

• TMY3toTMY2: converts TMY3 files to TMY2 format.

  • Windows version; documentation is included in the ZIP files.
    • TMY3toTMY2.zip - User interface version with easy configuration and file selection
    • TMY3toTMY2_cmd.zip - Command line version for batch processing multiple files
  • ANSI C version
    • TMY3toTMY2_ansi.c

      NOTE:
      Users who downloaded TMY3toTMY2_ansi.c before 1625 GMT on 11 July 2008 will find
      that the string.h header file is included twice. The code will compile but will not
      properly report latitude and longitude. One instance of string.h should be
      replaced with math.h before compiling. This has been corrected in the code now
      available for download.